% Power estimation on discrete signals
function [y,yf] = rms(x,Nw,yi)

N = length(x);
y = zeros(1,N);


Nb = ceil(N/Nw);
xp = zeros(1,Nb*Nw);
yp = zeros(1,Nb*Nw);

xp(1:N) = x(1:N);
yp(1) = abs(x(1));

for k = 1:Nb-1,
  for n = (k-1)*Nw+2:k*Nw+2,
    yp(n) = yp(n-1)*(1-1/Nw) + 1/Nw*abs(x(n));
  end;
end;

y = yp(1:N);